U.S. Pat. No. 7,218,281 to Daniel Sievenpiper et al. “Artificial Impedance Structure” filed Jul. 1, 2005, discloses how to create a scalar impedance function using a holographic principle. However, artificial impedance surfaces characterized by a scalar impedance lack polarization control.
The method of constructing an artificial impedance surface characterized by a scalar impedance for the controlled scattering of a surface wave (with no polarization control) is disclosed in U.S. application Ser. No. 11/173,182 “Artificial Impedance Structure” by Daniel Sievenpiper et al, filed Jul. 1, 2005. An artificial impedance surface with an impedance modulation created from the interference of surface wave and outgoing wave is constructed from metal patterning on a dielectric substrate.
The prior art for artificial impedance surfaces used only scalar impedances with no polarization control. With a impedance surface characterized by a scalar impedance, only a single mode of the impedance surface is controlled at once, with no regard for the cross-polarization generated by the impedance surface.